Cisco 2950G 24 Software Configuration Guide - Page 192
Configuring NTP Access Restrictions, Creating an Access Group and Assigning a Basic IP Access List
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Managing the System Time and Date Chapter 7 Administering the Switch Step 6 Step 7 Command copy running-config startup-config Purpose (Optional) Save your entries in the configuration file. Configure the connected peers to receive NTP broadcast packets as described in the next procedure. To disable the interface from sending NTP broadcast packets, use the no ntp broadcast interface configuration command. This example shows how to configure an interface to send NTP version 2 packets: Switch(config)# interface gigabitethernet0/1 Switch(config-if)# ntp broadcast version 2 Beginning in privileged EXEC mode, follow these steps to configure the switch to receive NTP broadcast packets from connected peers: Step 1 Step 2 Command configure terminal interface interface-id Step 3 ntp broadcast client Step 4 exit Step 5 ntp broadcastdelay microseconds Step 6 Step 7 Step 8 end show running-config copy running-config startup-config Purpose Enter global configuration mode. Specify the interface to receive NTP broadcast packets, and enter interface configuration mode. Enable the interface to receive NTP broadcast packets. By default, no interfaces receive NTP broadcast packets. Return to global configuration mode. (Optional) Change the estimated round-trip delay between the switch and the NTP broadcast server. The default is 3000 microseconds; the range is 1 to 999999. Return to privileged EXEC mode. Verify your entries. (Optional) Save your entries in the configuration file. To disable an interface from receiving NTP broadcast packets, use the no ntp broadcast client interface configuration command. To change the estimated round-trip delay to the default, use the no ntp broadcastdelay global configuration command. This example shows how to configure an interface to receive NTP broadcast packets: Switch(config)# interface gigabitethernet0/1 Switch(config-if)# ntp broadcast client Configuring NTP Access Restrictions You can control NTP access on two levels as described in these sections: • Creating an Access Group and Assigning a Basic IP Access List, page 7-41 • Disabling NTP Services on a Specific Interface, page 7-42 7-40 Catalyst 2950 Desktop Switch Software Configuration Guide 78-14982-01
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